The Dotted-Board Model: A new MIP model for nesting irregular shapes

• Type: Article in International Scientific Journal
• Date: 2013

Authors

Franklina M B Toledo (Author) Other; Maria Antonia Carravilla (Author) FEUP; Cristina Ribeiro (Author) FEUP; Jose F Oliveira (Author) FEUP; Miguel M Gomes (Author) FEUP

Journal

Title: International Journal of Production Economics

Vol. 145 No. 2

Pages: 478-487

ISSN: 0925-5273

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 40 Citations

ISI Web of Science

Scopus - 56 Citations

Scientific classification

CORDIS: Technological sciences > Engineering > Industrial engineering

FOS: Engineering and technology > Civil engineering

Other information

Authenticus ID: P-006-6QV

DOI: 10.1016/j.ijpe.2013.04.009

Abstract (EN): The nesting problem, also known as irregular packing problem, belongs to the generic class of cutting and packing (C&P) problems. It differs from other 2-D C&P problems in the irregular shape of the pieces. This paper proposes a new mixed-integer model in which binary decision variables are associated with each discrete point of the board (a dot) and with each piece type. It is much more flexible than previously proposed formulations and solves to optimality larger instances of the nesting problem, at the cost of having its precision dependent on board discretization. To date no results have been published concerning optimal solutions for nesting problems with more than 7 pieces. We ran computational experiments on 45 problem instances with the new model, solving to optimality 34 instances with a total number of pieces ranging from 16 to 56, depending on the number of piece types, grid resolution and the size of the board. A strong advantage of the model is its insensitivity to piece and board geometry, making it easy to extend to more complex problems such as non-convex boards, possibly with defects. Additionally, the number of binary variables does not depend on the total number of pieces but on the number of piece types, making the model particularly suitable for problems with few piece types. The discrete nature of the model requires a trade-off between grid resolution and problem size, as the number of binary variables grows with the square of the selected grid resolution and with board size.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10